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Diffstat (limited to 'src/complete.c')
| -rw-r--r-- | src/complete.c | 283 |
1 files changed, 283 insertions, 0 deletions
diff --git a/src/complete.c b/src/complete.c new file mode 100644 index 0000000..9e91400 --- /dev/null +++ b/src/complete.c @@ -0,0 +1,283 @@ +/* +** 2001 September 15 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +** An tokenizer for SQL +** +** This file contains C code that implements the sqlite3_complete() API. +** This code used to be part of the tokenizer.c source file. But by +** separating it out, the code will be automatically omitted from +** static links that do not use it. +*/ +#include "sqliteInt.h" +#ifndef SQLITE_OMIT_COMPLETE + +/* +** This is defined in tokenize.c. We just have to import the definition. +*/ +#ifndef SQLITE_AMALGAMATION +#ifdef SQLITE_ASCII +#define IdChar(C) ((sqlite3CtypeMap[(unsigned char)C]&0x46)!=0) +#endif +#ifdef SQLITE_EBCDIC +extern const char sqlite3IsEbcdicIdChar[]; +#define IdChar(C) (((c=C)>=0x42 && sqlite3IsEbcdicIdChar[c-0x40])) +#endif +#endif /* SQLITE_AMALGAMATION */ + + +/* +** Token types used by the sqlite3_complete() routine. See the header +** comments on that procedure for additional information. +*/ +#define tkSEMI 0 +#define tkWS 1 +#define tkOTHER 2 +#ifndef SQLITE_OMIT_TRIGGER +#define tkEXPLAIN 3 +#define tkCREATE 4 +#define tkTEMP 5 +#define tkTRIGGER 6 +#define tkEND 7 +#endif + +/* +** Return TRUE if the given SQL string ends in a semicolon. +** +** Special handling is require for CREATE TRIGGER statements. +** Whenever the CREATE TRIGGER keywords are seen, the statement +** must end with ";END;". +** +** This implementation uses a state machine with 8 states: +** +** (0) INVALID We have not yet seen a non-whitespace character. +** +** (1) START At the beginning or end of an SQL statement. This routine +** returns 1 if it ends in the START state and 0 if it ends +** in any other state. +** +** (2) NORMAL We are in the middle of statement which ends with a single +** semicolon. +** +** (3) EXPLAIN The keyword EXPLAIN has been seen at the beginning of +** a statement. +** +** (4) CREATE The keyword CREATE has been seen at the beginning of a +** statement, possibly preceeded by EXPLAIN and/or followed by +** TEMP or TEMPORARY +** +** (5) TRIGGER We are in the middle of a trigger definition that must be +** ended by a semicolon, the keyword END, and another semicolon. +** +** (6) SEMI We've seen the first semicolon in the ";END;" that occurs at +** the end of a trigger definition. +** +** (7) END We've seen the ";END" of the ";END;" that occurs at the end +** of a trigger difinition. +** +** Transitions between states above are determined by tokens extracted +** from the input. The following tokens are significant: +** +** (0) tkSEMI A semicolon. +** (1) tkWS Whitespace. +** (2) tkOTHER Any other SQL token. +** (3) tkEXPLAIN The "explain" keyword. +** (4) tkCREATE The "create" keyword. +** (5) tkTEMP The "temp" or "temporary" keyword. +** (6) tkTRIGGER The "trigger" keyword. +** (7) tkEND The "end" keyword. +** +** Whitespace never causes a state transition and is always ignored. +** This means that a SQL string of all whitespace is invalid. +** +** If we compile with SQLITE_OMIT_TRIGGER, all of the computation needed +** to recognize the end of a trigger can be omitted. All we have to do +** is look for a semicolon that is not part of an string or comment. +*/ +int sqlite3_complete(const char *zSql){ + u8 state = 0; /* Current state, using numbers defined in header comment */ + u8 token; /* Value of the next token */ + +#ifndef SQLITE_OMIT_TRIGGER + /* A complex statement machine used to detect the end of a CREATE TRIGGER + ** statement. This is the normal case. + */ + static const u8 trans[8][8] = { + /* Token: */ + /* State: ** SEMI WS OTHER EXPLAIN CREATE TEMP TRIGGER END */ + /* 0 INVALID: */ { 1, 0, 2, 3, 4, 2, 2, 2, }, + /* 1 START: */ { 1, 1, 2, 3, 4, 2, 2, 2, }, + /* 2 NORMAL: */ { 1, 2, 2, 2, 2, 2, 2, 2, }, + /* 3 EXPLAIN: */ { 1, 3, 3, 2, 4, 2, 2, 2, }, + /* 4 CREATE: */ { 1, 4, 2, 2, 2, 4, 5, 2, }, + /* 5 TRIGGER: */ { 6, 5, 5, 5, 5, 5, 5, 5, }, + /* 6 SEMI: */ { 6, 6, 5, 5, 5, 5, 5, 7, }, + /* 7 END: */ { 1, 7, 5, 5, 5, 5, 5, 5, }, + }; +#else + /* If triggers are not supported by this compile then the statement machine + ** used to detect the end of a statement is much simplier + */ + static const u8 trans[3][3] = { + /* Token: */ + /* State: ** SEMI WS OTHER */ + /* 0 INVALID: */ { 1, 0, 2, }, + /* 1 START: */ { 1, 1, 2, }, + /* 2 NORMAL: */ { 1, 2, 2, }, + }; +#endif /* SQLITE_OMIT_TRIGGER */ + + while( *zSql ){ + switch( *zSql ){ + case ';': { /* A semicolon */ + token = tkSEMI; + break; + } + case ' ': + case '\r': + case '\t': + case '\n': + case '\f': { /* White space is ignored */ + token = tkWS; + break; + } + case '/': { /* C-style comments */ + if( zSql[1]!='*' ){ + token = tkOTHER; + break; + } + zSql += 2; + while( zSql[0] && (zSql[0]!='*' || zSql[1]!='/') ){ zSql++; } + if( zSql[0]==0 ) return 0; + zSql++; + token = tkWS; + break; + } + case '-': { /* SQL-style comments from "--" to end of line */ + if( zSql[1]!='-' ){ + token = tkOTHER; + break; + } + while( *zSql && *zSql!='\n' ){ zSql++; } + if( *zSql==0 ) return state==1; + token = tkWS; + break; + } + case '[': { /* Microsoft-style identifiers in [...] */ + zSql++; + while( *zSql && *zSql!=']' ){ zSql++; } + if( *zSql==0 ) return 0; + token = tkOTHER; + break; + } + case '`': /* Grave-accent quoted symbols used by MySQL */ + case '"': /* single- and double-quoted strings */ + case '\'': { + int c = *zSql; + zSql++; + while( *zSql && *zSql!=c ){ zSql++; } + if( *zSql==0 ) return 0; + token = tkOTHER; + break; + } + default: { +#ifdef SQLITE_EBCDIC + unsigned char c; +#endif + if( IdChar((u8)*zSql) ){ + /* Keywords and unquoted identifiers */ + int nId; + for(nId=1; IdChar(zSql[nId]); nId++){} +#ifdef SQLITE_OMIT_TRIGGER + token = tkOTHER; +#else + switch( *zSql ){ + case 'c': case 'C': { + if( nId==6 && sqlite3StrNICmp(zSql, "create", 6)==0 ){ + token = tkCREATE; + }else{ + token = tkOTHER; + } + break; + } + case 't': case 'T': { + if( nId==7 && sqlite3StrNICmp(zSql, "trigger", 7)==0 ){ + token = tkTRIGGER; + }else if( nId==4 && sqlite3StrNICmp(zSql, "temp", 4)==0 ){ + token = tkTEMP; + }else if( nId==9 && sqlite3StrNICmp(zSql, "temporary", 9)==0 ){ + token = tkTEMP; + }else{ + token = tkOTHER; + } + break; + } + case 'e': case 'E': { + if( nId==3 && sqlite3StrNICmp(zSql, "end", 3)==0 ){ + token = tkEND; + }else +#ifndef SQLITE_OMIT_EXPLAIN + if( nId==7 && sqlite3StrNICmp(zSql, "explain", 7)==0 ){ + token = tkEXPLAIN; + }else +#endif + { + token = tkOTHER; + } + break; + } + default: { + token = tkOTHER; + break; + } + } +#endif /* SQLITE_OMIT_TRIGGER */ + zSql += nId-1; + }else{ + /* Operators and special symbols */ + token = tkOTHER; + } + break; + } + } + state = trans[state][token]; + zSql++; + } + return state==1; +} + +#ifndef SQLITE_OMIT_UTF16 +/* +** This routine is the same as the sqlite3_complete() routine described +** above, except that the parameter is required to be UTF-16 encoded, not +** UTF-8. +*/ +int sqlite3_complete16(const void *zSql){ + sqlite3_value *pVal; + char const *zSql8; + int rc = SQLITE_NOMEM; + +#ifndef SQLITE_OMIT_AUTOINIT + rc = sqlite3_initialize(); + if( rc ) return rc; +#endif + pVal = sqlite3ValueNew(0); + sqlite3ValueSetStr(pVal, -1, zSql, SQLITE_UTF16NATIVE, SQLITE_STATIC); + zSql8 = sqlite3ValueText(pVal, SQLITE_UTF8); + if( zSql8 ){ + rc = sqlite3_complete(zSql8); + }else{ + rc = SQLITE_NOMEM; + } + sqlite3ValueFree(pVal); + return sqlite3ApiExit(0, rc); +} +#endif /* SQLITE_OMIT_UTF16 */ +#endif /* SQLITE_OMIT_COMPLETE */ |